<style>
    body{
        margin:0px;
        padding:0px;
    }
    .top{
        margin:0px;
        padding:0px;
        width:100%;
        height: 80px;
        background: dodgerblue;
        color:white;
        font-size:18px;
        font-weight: bold;
        line-height: 80px;

    }
</style>
<div class="top">
    <span style="margin-left: 20px;">梦网-前端案例集合</span>
</div>
